Experimentelle Untersuchungen der magnetischen Wechselwirkungen und Anisotropie in 3d-4f heterometallischen Systemen
Zusammenfassung der Projektergebnisse
In this project, high frequency-electron paramagnetic resonance (HF-EPR) measurements were carried out for the various single molecular magnet (SMM) candidate inorganic chemical complexes. From the HF-EPR data, spin Hamiltonian parameters for the complexes, i.e. gfactors, axial (D) and transverse (E) anisotropy, and J exchange interaction, are unambiguously determined. For the 3d metallacrown complexes, Cu4Cu ((HNEt3)2Cu(II)[12-MCCu(II)N(Shi)-4]) and Co4Co ((HPip)(Piv)[Li[Co(II)(μ2-Piv)2(Piv)[ 12-MCCo(III)N(Shi)-4](Pip)5]]2), the ground spin state of the complexes with the antiferromagnetic couplings between the magnetic ions was confirmed. Also the g-factor and magnetic anisotropy were clarified. In the study for a single crystal of [DyIII{NiII(L)}2]ClO4 complex which has two differently oriented magnetic ion axes, the spin Hamiltonian parameters including JDy-Ni and JNi-Ni interactions are precisely obtained in consideration of Euler angle and Ising spin concept. HF-EPR studies on [V(DAPBH)(CH3OH)2]Cl·CH3OH and [Co(L1)4]X2, where L 1 = thiourea (NH2CSNH2) and X = I, Br, and [Co(L1)4](SiF6) complexes experimentally revealed the intermolecular interaction in the monomer complexes and elucidated the contribution of the interactions to the magnetic property of the complexes. For the (Et3NH)[Er(H2DAPS)Cl2] (H4DAPS = 2,6-diacetylpyridine bis- (salicylhydrazone)) complex, the energy level diagram of the lanthanide magnetic ion complex as a function of the magnetic field was speculated based on the EPR data and supported by the crystal field calculation results. In the study on two CoII complexes, namely square pyramidal (Co-SP) and trigonal bipyramidal (Co-TBP) five-coordinate CoII complexes with the general molecular formula of [Co(DPPE)2Cl]SnCl3, based on the EPR data, the direct association of the differences in g-anisotropy to the distinct relaxation behaviors of these low-spin S = ½ complexes was elucidated. Although COVID19 pandemic impedes all the project progress and researches, various complexes have been studied by means of HF-EPR measurements, and extended studies including the HF-EPR studies on the exchange interaction between the magnetic ions in 3d-4f heterometallic complexes will be reported in close time period.
Projektbezogene Publikationen (Auswahl)
- Jour. Mag. Mag. Mat. 477, 340 (2019)
C. Koo, J. Park, J. Butscher, E. Rentschler, and R. Klingeler
(Siehe online unter https://doi.org/10.1016/j.jmmm.2019.01.038) - Dalton Trans. 49, 15287 (2020)
T. A. Bazhenova, L. V. Zorina, S. V. Simonov, V. S. Mironov, O. V. Maximova, L. Spillecke, C. Koo, R. Klingeler, Y. V. Manakin, A. N. Vasiliev, and E. B. Yagubskii
(Siehe online unter https://doi.org/10.1039/d0dt03092a) - Chem. Eur. J. 27, 9372 (2021)
P. Comba, M. Enders, M. Großhauser, M. Hiller, R. Klingeler, C. Koo, D. Müller, G. Rajaraman, A. Swain, M. Tavhelidse, and H. Wadepohl
(Siehe online unter https://doi.org/10.1002/chem.202100626) - Dalton Trans. 50, 18143 (2021)
L. Spillecke, C. Koo, O. Maximova, V. S. Mironov, V. A. Kopotkov, D. V. Korchagin, A. N. Vasiliev, E. B. Yagubskii, and R. Klingeler
(Siehe online unter https://doi.org/10.1039/d1dt03228c) - Polyhedron 208, 115389 (2021)
L. Spillecke, S. Tripathi, C. Koo, M. Ansari, S. Vaidya, A. Rasamsetty, T. Mallah, G. Rajaraman, M. Shanmugam, R. Klingeler
(Siehe online unter https://doi.org/10.1016/j.poly.2021.115389) - Inorg. Chem. 61, 317 (2022)
L. Spillecke, S. Tripathi, C. Koo, A. Bahr, A. Swain, R. Haldar, M. Ansari, J. Jasinski, G. Rajaraman, M. Shanmugam, and R. Klingeler
(Siehe online unter https://doi.org/10.1021/acs.inorgchem.1c02881)
